No, no ,no. You guys don't understand it. Couldn't you hunt for truck-kun instead?
kill it and dissect for it's parts. If you found it's 'isekai transmigration engine' collect it and prepare to isekai. Then when no one notices it, go to a space station and slap the 'isekai engine' to Falcon 9 and ride to victory.
Now you don't need to worry for 'medieval' technology. You already have prepared to isekai after all with a space ship as a plus :D. If you're having doubts about the technology of your spaceship, all you need to do is to steal them magics and technologiez and do the enchanting-thingy.
You want harem and a place to live? Colonize and conquer
Perhaps there is an antagonistic/tyrant ruling force like a demon lord? Show them the taste of Liberation.
Oh god, I got out of topic...
Anyways just know how the isekai magic works by taking apart truck-kun and you don't need to get hit by it.